9 q 8 Brenchley . — The Development of the Grain of Barley. 
This rise is much more evident than with wheat, because of the longer 
maturation period, during which the migration into the grain has practically 
ceased while respiration is still continuing, though probably slowing off 
gradually. The loss due to respiration falls altogether on the non-nitro- 
genous (carbohydrate) constituents of the grain, hence the relative increase 
in the proportion of nitrogen present. While the figures at the earlier 
periods indicate a considerable rise in the proportion of nitrogen in the grain 
before any great decrease has occurred in the amount of material entered, 
still there is not sufficient evidence to prove any change in the proportion of 
nitrogen actually taken in by the plant, since as development continues the 
0 3 6 9 12 15 18 21 £4 2,7 30 33 35 39 4£ 45 48 Days 
Fig. 6. Percentage of protein nitrogen in total nitrogen. 
quantity of respiring substance becomes much greater, causing a correspond- 
ing increase in the amount of non-nitrogenous material broken down, so 
entailing a consequent rise in the percentage of nitrogenous material present. 
Fig. 6 shows the results of estimating the proportion of protein nitrogen 
in total nitrogen. The curves, when smoothed, seem to indicate a slow but 
steady rise up to about a fortnight before cutting, followed by a period in 
which the protein nitrogen is either constant or slightly falling off. The 
actual non-protein nitrogen in 1,000 grains (Fig. 7), though very erratic, 
tends to increase gradually all along the line. 
Ash and phosphoric acid . The proportion of ash to dry matter (Fig. 8) 
is considerably higher in the two normal plots A and B than in the P 2 0 5 - 
starved plot C. In the first two the proportion falls steadily for six periods 
